Ecogenômica de archaea e monitoramento de comunidades de procariotos redutores de sulfato: aplicações na indústria de petróleo e gás

The human activities responsible for the ambient degradation in the modern world are diverse. The industrial activities are preponderant in the question of the impact consequences for brazilian ecosystems. Amongst the human activities, the petroliferous industry in operation in Potiguar Petroliferous Basin (PPB) displays the constant risk of ambient impacts in the integrant cities, not only for the human populations and the environment, but also it reaches the native microorganisms of Caatinga ground and in the mangrove sediment. Not hindering, the elaboration of strategies of bioremediation for impacted areas pass through the knowledge of microbiota and its relations with the environment. Moreover, in the microorganism groups associated to oil, are emphasized the sulfate-reducing prokaryotes (SRP) that, in its anaerobic metabolism, these organisms participate of the sulfate reduction, discharging H2S, causing ambient risks and causing the corrosion of surfaces, as pipelines and tanks, resulting in damages for the industry. Some ancestries of PRS integrate the Archaea domain, group of microorganisms whose sequenced genomes present predominance of extremophilic adaptations, including surrounding with oil presence. This work has two correlated objectives: i) the detection and monitoring of the gene dsrB, gift in sulfate-reducing prokaryotes, through DGGE analysis in samples of mDNA of a mangrove sediment and semiarid soil, both in the BPP; ii) to relate genomic characteristics to the ecological aspects of Archaea through in silico studies, standing out the importance to the oil and gas industry. The results of the first work suggest that the petrodegraders communities of SRP persist after the contamination with oil in mangrove sediment and in semiarid soil. Comparing the populations of both sites, it reveals that there are variations in the size and composition during one year of experiments. In the second work, functional and structural factors are the probable cause to the pressure in maintenance of the conservation of the sequences in the multiple copies of the 16S rDNA gene. Is verified also the discrepancy established between total content GC and content GC of the same gene. Such results relating ribosomal genes and the ambient factors are important for metagenomic evaluations using PCR-DGGE. The knowledge of microbiota associated to the oil can contribute for a better destination of resources by the petroliferous industry and the development of bioremediation strategies. Likewise, search to lead to the best agreement of the performance of native microbiota in biogeochemical cycles in Potiguar Petroliferous Basin ecosystem

Calçadas invisíveis: aspectos do passeio público, em Natal-RN, como projeção de uma cidadania ausente

This study has as a goal to establish a relationship between public sidewalk characteristics of Lagoa Nova District (neighborhood), in Natal and the kind of citizens whose constructions and maintenance layouts reflects. It‟s understood here as public sidewalk, specifically, the place reserved for passers-by traffic, located between public lots and vehicles pavements. It‟s a concern to make a brief survey about the occupation of this particular region and a detailed description over physical characteristic of its sidewalks that shows several obstacles for passers-by accessibility, trying to find possible factors that explain the problematic format , once, at the first sight, most of accessibility of passers-by is compromised. It‟ also, searched, local population thoughts regarding occupation notions about this environment, just like as cultural, political and economical aspects that might influence upon snatching these hybrid places located between private and public border line. It‟s confirmed that the nowadays sidewalks‟ shapes is not only citizenship reflection or a lack of it but shows it as an active agent related with the construction of this set of fundamental rights and duties vital for harmonical co-living local citizens

Acordos internacionais sobre a produção compartilhada de recursos naturais: a unitização interestatal na área do petróleo e gás sob o enfoque constitucional brasileiro

The apportionment of natural resources between sovereign States is a subject that relates many aspects of International law, as long as Constitutional Law, at the execution and application phases of international treaties that regulates the exploration of common goods. In this sense, because of their natural characteristics that creates an environment of constant migration and fixation in transboundary regions, terrestrial or maritime, the petroleum and the natural gas bound a complex juridical apparatus that can control the sovereign rights involved. This research is aim at accomplishing a study concerning the international agreements that enable the non-unilateral action, specifically the unitization treaties between sovereign States, as a manner to resolve situations related to the individualization of oil and/or gas reservoirs that go across their national borders. These agreements will be analyzed considering the international public law sources theory, bearing in mind yet the already existed experiences in this sense, not disregarding the way that this fact could affect Brazil. It will begin with an historical incursion over the unitization institute, covering its main characteristics and its formation and execution procedures, and finally it will address the Brazilian legal system and the comparative law threats the institute. The clauses of these relevant agreements will be analyzed in details, concerning its particularities and its contents. Because these agreements are international obligatory rules of law, it is indispensable that they are considered under the auspices of the international law system, focusing their nature and the subjects of international law and establishing them as sources of the international law, analyzing them, then, as international rules and the applicable law to these juridical relations, the conventional established, the consolidated international custom and the applicable International Law principles, appearing the State s responsibility as an important subject for the verification of the acts lawful practiced by States. The analysis of the apportionment of these natural resources ends with the individualization of possible exploitable marine oil fields located between the exclusive economic zone and the continental platform ends and the region administrated by the International Seabed Authority. At last, the Brazilian constitutional system appears as the mechanism of integration, application and execution of the international unitization agreements in Brazil, detaching the format and the proceedings that the international treaties take to acquire validity at the national legal system, passing through the treaties interpretation and the applicable constitutional principles, coming to its application in Brazil, considering the existing constitutional peculiarities and the role played by the National Agency of Petroleum, Natural Gas and bio-fuel ANP

O princípio constitucional do desenvolvimento e a utilização de recursos hídricos na indústria de petróleo

As can be inferred by the title of its study The constitutional principle of sustainable development and the utilization of hidrical resources in the oil industry the transcribed pages are dedicated to the approach of the mentioned subjects which, despite being apparently different, will be shown intrinsically connected as goes by the study. The superation of this first step by the reader will lead to an important perception of the title: that the situation requires, urgently, a defined posture, a complete conduct change and, therefore, a modification of the paradigms currently establisheds. To brake barriers, modifying what is lived by, is the ultimate goal. For that, there is no unique path, linear, but there were broached the development themes, the hidrical resources theme and oil and natural gas industry at the necessary points to achieve, by the end, a comprehension for the Brazilian Federal Republic goals in the search for the application of these juridical norms. The ones whom lay down over this study shall notice that, more than a simple approach over these themes (which are still less worked and searched in Brazil), the heavy critic of an instituted and pacifically accepted reality, directly offensive of the constitutional principles. The debate evolves from punctual and specific aspects, it gains life, flies, searching how the juridical order equalizes the economic model to the environment defense. Standing by the possibility of conciliation among constitutional principles, the remodeling of an economic segment is defended, aligning it to the sustainable limits. Development, sustainable, becomes means and goals to the implementation of liberty, capacitating everyone to achieve their goals of life, their libertments, fruit of the inherent antagonism of the Constitution the sustainable development offers, while an axiological vector, a new reality to the economic order, turning it into a motriz element to the fortification of constitutional normative force and for the national development

Análise jurídico-constitucional do fomento aos campos maduros de produção de petróleo no Brasil

The oil activities in Brazil had been started in an intensive way in the end of the 30 s and in the beginning of the 40 s. Many of the brazilians fields discovered in the past are nowadays in decline. They are called ―mature fields‖. These fields, because of the decline situation that characterizes them, are not interesting for the majors. The majors want the big fields and big productions. On the other hand, they could be interesting for the small and medium enterprises. The mature oil fields are instruments of development, they have oil and the oil production is an activity connected with many social and economics benefits: jobs, taxes, royalties, etc. The Brazilian State, in this context, needs to realize actions to promote the activities in the mature oil fields, especially with the work of the small and mediums enterprises. Many of the onshore brazilian mature fields are located at the Northeast, a region matched by many social and economic problems. The activities in the mature fields of the Northeast Region could solve some of its problems. The present research analyses the mature oil fields and its situations in Brazil, making criticisms and suggestions. The methodology adopted is theoretical and descriptive, with literature review, case law and legislation (Constituição Federal de 1988, ―Law of the Oil‖). This research examines the following points: mature fields rounds and its documents, name and definition of the mature fields, definition of small and medium enterprises, environmental aspects, concentration of certain activities of the sector and the royalties

O princípio constitucional da eficiência aplicado à outorga e à cobrança da água produzida na exploração petrolífera

Water production is unavoidable during a petrol well s lifetime. The amount of produced water associated with oil varies a lot. It can reach values which account to 50% in volume up to nearly 100%, at the end of the well s economic life. It could be verified that, once the water reaches the productive wells, there must be a management of this produced water. Its destiny is defined after a precise study, after which the best option is chosen between relieving it into the environment, re-injecting it into the producing container or disposing it into non-producing formations. Whichever option is made by the involved professionals, after the necessary analysis, it shall consider, besides the technical and economical aspects, also the alternatives which entail less environmental impact. The purpose of the present research is to conduct a study about the application of the constitutional principle of efficiency on the instruments worked out by the public administration on water management, specifically the water use licence and charging for the use in the management of water resources applicable to water production at the petrol wells. In this attempt, before entering the proper approach of the efficiency of the mentioned instruments, it was necessary not only bring to light the doctrinal perception about the constitutional principle of administrative efficiency, but also make some considerations concerning to the structure of the national water resources management, set by the Federal Constitution (1988) and the federal legislation (9433/97)

Economia do petróleo e desenvolvimento: estudo exploratório sobre as perspectivas do pré-sal brasileiro

A pesquisa analisa as possibilidades abertas pela exploração de petróleo na camada pré-sal, avaliando de que maneira a expansão do setor petrolífero poderá acelerar o crescimento econômico brasileiro e contribuir para novas estratégias de desenvolvimento. A hipótese inicial é que o Brasil enfrenta uma restrição estrutural de balanço de pagamentos, que poderá ser amenizada pela diminuição das importações de petróleo e derivados e pelo aumento do valor exportado no setor. Para avaliá-la são resgatados aspectos históricos e geopolíticos relacionados ao petróleo, assim como são tratadas as características microeconômicas dos recursos naturais não renováveis. Também se consideram questões de ordem macroeconômica, como a especialização produtiva da economia brasileira e sua inserção no comércio internacional, discutindo como o desenvolvimento da indústria petrolífera poderá afetá-las. Para tanto, a investigação fundamenta-se na teoria estruturalista e nos modelos de crescimento com ênfase na restrição externa. O trabalho examina ainda os casos da Rússia, Venezuela e México para avaliar a experiência de países exportadores de petróleo. Como contribuição, um modelo de crescimento é utilizado para realizar simulações acerca do Brasil, cobrindo o período 2013-2020 com a formulação de três cenários. A partir dos resultados discute-se que a necessidade de consecução das metas fiscal e de inflação pode desencadear políticas restritivas que limitam a utilização da folga fiscal e externa, oriundas do pré-sal, para induzir o crescimento. Conclui-se que um círculo virtuoso de desenvolvimento com mudança estrutural depende não apenas da modernização produtiva, mas também, e principalmente, da evolução político-institucional do país

Gestão ambiental na indústria do petróleo : fatores associados ao comportamento pró-ambiental de empregados de uma empresa brasileira de óleo e gás

This survey develops a study about the pro-environment behavior of a brazilian company of oil and gas sector, emphazing the Petróleo Brasileiro S/A PETROBRAS in its Unit of Business of Exploration and Production in the State of Rio Grande do Norte and Ceará − UN-RNCE. The work s development adopt the bibliographic research methodology with the descriptive exploratory analisys, with the purpouse of identifying related points with the knowledge and the analysed enterprise s staff conduct, by the aplication of the interview with a instrument of data colecting with closed variable questions from answers that varies from o to 10.The answers allowed us to know the employees knowledge about the related aspects of environmental responsability, knowing also the involvement of the employees with the politics of environmental managment that has been implemented in the operating area of the company. The research led us to an important verification of the pro-environmental behavior of the people interviewed. The results depends of a wise acting, not only inside the company, but also outside, where the results of this acting will be more perceived for the society. Finally, we conclude that the company has a politics of management with a great importance, emphasinzing that the employees are been in constant training about their behavior resulting in satisfaction

Desenvolvimento de um software de comunicação sem fio aplicado à instrumentação de unidade de elevação de petróleo tipo Plunger Lift

This dissertation aims to develop a software applied to a communication system for a wireless sensor network (WSN) for tracking analog and digital variables and control valve of the gas flow in artificial oil s elevation units, Plunger Lift type. The reason for this implementation is due to the fact that, in the studied plant configuration, the sensors communicate with the PLC (Programmable and Logic Controller) by the cables and pipelines, making any changes in that system, such as changing the layout of it, as well as inconveniences that arise from the nature of the site, such as the vicinity s animals presence that tend to destroy the cables for interconnection of sensors to the PLC. For software development, was used communication polling method via SMAC protocol (Simple Medium Access ControlIEEE 802.15.4 standard) in the CodeWarrior environment to which generated a firmware, loaded into the WSN s transceivers, present in the kit MC13193-EVK, (all items described above are owners of Freescale Semiconductors Inc.). The network monitoring and parameterization used in its application, was developed in LabVIEW software from National Instruments. The results were obtained through the observation of the network s behavior of sensors proposal, focusing on aspects such as: indoor and outdoor quantity of packages received and lost, general aspects of reliability in data transmission, coexistence with other types of wireless networks and power consumption under different operating conditions. The results were considered satisfactory, which showed the software efficiency in this communication system

Análise de confiabilidade de uma bomba centrífuga: aplicação na injeção de água para recuperação de petróleo

The oil industry`s need to produce with maximum efficiency, not to mention the safety and the environment aspects, encourages the optimization of processes. It makes them look for a level of excellence in acquisition of equipment, ensuring the quality without prejudice security of facilities and peoples. Knowing the reliability of equipment and that this stands for a system is fundamental to the production strategy to seeks the maximum return on investment. The reliability analysis techniques have been increasingly applied in the industry as strategy for predicting failures likelihood ensuring the integrity of processes. Some reliability theories underlie the decisions to use stochastic calculations to estimate equipment failure. This dissertation proposes two techniques associating qualitative (through expertise opinion) and quantitative data (European North Sea oil companies fault database, Ored) applied on centrifugal pump to water injection system for secondary oil recovery on two scenarios. The data were processed in reliability commercial software. As a result of hybridization, it was possible to determine the pump life cycle and what impact on production if it fails. The technique guides the best maintenance policy - important tool for strategic decisions on asset management.

Caracterização do óleo de carnaúba para uso como biolubrificante

Lubricant is responsible for reducing the wear on the friction protect the metal against oxidation, corrosion and dissipates excess heat, making it essential for the balance of a mechanical system, consequently prolonging the useful life of such a system. The origin of lubricating oils is usually mineral being extracted from the petroleum. But the search for a new source of production of lubricants and fuels it is necessary to meet future demands and reduce the possible environmental damage. For this reason, looking alternative means to produce certain products derived from petroleum, such as biodiesel, for example. Returning to the realm of lubricants, also one realizes this need for new raw materials for their production. Vegetable oil is a renewable resource and biodegradable, and its use entails advantages in environmental, social and economic. The development of this project aims to characterize the carnauba oil as a lubricant plant, or biolubricant. To analyze the oil carnauba tests as checking density, flash point, fire point, viscosity, viscosity, acid number, pH, copper corrosion, thermal conductivity and thermal resistivity were developed. In addition, for conducting the wear on the friction and the gradient of the system temperature, the analysis equipment is designed for wear on the friction. Based on these results, it is observed that the oil carnauba show good correlation to its application as biolubricant

Estudo de sistemas microemulsionados utilizando água do mar na recuperação avançada de petróleo

Petroleum exists in the nature in certain underground formations where it is adsorbed into the rocks pores. For the conventional recovery methods usually only 30% of the oil is extracted and this can be credited, basically, to three aspects: high viscosity of the oil, geology of the formation and high interfacial tensions between the reservoir s fluids. The enhanced recovery methods use the injection of a fluid or fluids mixture in a reservoir to act in points where the conventional process didn't reach the recovery rates. Microemulsion flooding, considered an enhanced method, has the purpose to desorb the oil from the rock formation and to attain an efficient displacement of the oil emulsion. With this in mind, this work was accomplished with two main objectives: the study of the parameters effect that influence a microemulsified system (surfactant and cosurfactant types, C/S rate and salinity) and the evaluation of displacement efficiency with the microemulsions that showed stability in the rich aqueous area. For the analyzed parameters it was chose the microemulsions composition used in the recovery stage: 25% water, 5% kerosene, 46.7% of butanol as cosurfactant and 23.3% of BC or SCO cosurfactant. The core plugs of Assu and Botucatu sandstones were appraised in porosity and permeability tests and then submitted to the steps of saturation with seawater and oil, conventional recovery with water and enhanced recovery with the selected microemulsions. The Botucatu sandstone presented better recovery parameters, and the microemulsion composed with BS surfactant had larger recovery efficiency (26.88%)

Estudo da viabilidade da destilação solar para polimento de águas produzidas de petróleo

This work study of solar distillation feasibility in effluent of petroleum industry: produced water, making possible your reuse for irrigation of oleaginous cultures or fodder crops or in steam generation, as well the transport phenomena involved. The methodology for development of this project was to characterize the effluent to be treated and to accomplish physical and chemical analysis in the distilled, to build distillation equipment, concomitant operation of both equipments and implementation of data processing and economical evaluation. The methodology used for all parameters is outlined in APHA (1998) and sampling of the type compound. The feeding of distillation equipment was performed with treated effluent from UTPF of Guamaré. The temperature was monitored throughout the distillers and during the time of operation. The distillers feed occur, as a rule, for sifon. The distillers were operated by a period of 17 months between July 2007 and February 2009, in which 40 experiments were performed. The radiation and temperature datas were acquired in the INPE s site and the temperature inside of the distillers was registered by DATALOGGER Novus. The rates of condensation (mL / min) were determined by measuring of the flow in a graduate test tube of 10 mL and a chronometer. We used two simple solar effect distillers of passive type with different angles in coverage: 20 ° and 45 °. The results obtained in this study and the relevant discussions are divided into six topics: sample characterization and quality of distilled; construction of distillers; operation (data, temperature profile), climatic aspects, treatment of data and economical analysis. Results obtained can be inferred that: the energy loss by the adoption of vessel glass was not significant, however, complicates the logistics of maintenance the equipment on a large scale. In the other hand, the surface of the tub with a glass shield on the equipment deterioration, both devices showed similar performance, so there is not justified for use of equipment 450. With regard to the climatological study it was verified that the Natal city presents monthly medium radiation varying in a range between 350 and 600 W/m2, and medium of wind speed of 5 m / s. The medium humidity is around 70% and rainfall is very small. The regime of the system is transient and although it has been treated as a stationary system shows that the model accurately represents the distillers system's 20 degrees. The quality of the distilled with regard to the parameters evaluated in this study is consistent with the Class 3 waters of CONAMA (Resolution 357). Therefore we can conclude that solar distillation has viability for treat oilfield produced water when considered the technical and environmental aspects, although it is not economically viable

Litoestratigrafia e deformação cenzóica na região de Icapuí, Ceará, e implicações para a estruturação de campos de petróleo na borda ocidental da bacia Potiguar(NE do Brasil)

This thesis deals with the sedimentological/stratigraphic and structural evolution of the sedimentary rocks that occur in the NW continental border of the Potiguar Basin. These rocks are well exposed along coastal cliffs between the localities of Lagoa do Mato and Icapuí, Ceará State (NE Brazil). The sedimentological/stratigraphic study involved, at the outcrop scale, detailed facies descriptions, profile mapping of the vertical succession of different beds, and columnar sections displaying inferred lateral relationships. The approach was complemented by granulometric and petrographic analyses, including the characterization of heavy mineral assemblages. The data set allowed to recognize two kinds of lithological units, a carbonate one of very restricted occurrence at the base of the cliffs, and three younger, distinct siliciclastic units, that predominate along the cliffs, in vertical and lateral extent. The carbonate rocks were correlated to the late Cretaceous Jandaíra Formation, which is covered by the siliciclastic Barreiras Formation. The Barreiras Formation occurs in two distinct structural settings, the usual one with nondeformed, subhorizontal strata, or as tilted beds, affected by strong deformation. Two lithofacies were recognized, vertically arranged or in fault contacts. The lower facies is characterized by silty-argillaceous sandstones with low-angle cross bedding; the upper facies comprises medium to coarse grained sandstones, with conglomeratic layers. The Tibau Formation (medium to coarse-grained sandstones with argillite intercalations) occurs at the NW side of the studied area, laterally interlayered with the Barreiras Formation. Eolic sediments correlated to the Potengi Formation overly the former units, either displaying an angular unconformity, or simply an erosional contact (stratigraphic unconformity). Outstanding structural features, identified in the Barreiras Formation, led to characterize a neocenozoic stress field, which generated faults and folds and/or reactivated older structures in the subjacent late cretaceous (to paleogene, in the offshore basin) section. The structures recognized in the Barreiras Formation comprise two distinct assemblages, namely a main extensional deformation between the localities of Ponta Grossa and Redonda, and a contractional style (succeeded by oblique extensional structures) at Vila Nova. In the first case, the structural assemblage is dominated by N-S (N±20°Az) steep to gently-dipping extensional faults, displaying a domino-style or listric geometry with associated roll-over structures. This deformation pattern is explained by an E-W/WNW extension, contemporaneous with deposition of the upper facies of the Barreiras Formation, during the time interval Miocene to Pleistocene. Strong rotation of blocks and faults generated low-angle distensional faults and, locally, subvertical bedding, allowing to estimate very high strain states, with extension estimates varying between 40% up to 200%. Numerous detachment zones, parallel to bedding, help to acommodate this intense deformation. The detachment surfaces and a large number of faults display mesoscopic features analoguous to the ones of ductile shear zones, with development of S-C fabrics, shear bands, sigmoidal clasts and others, pointing to a hydroplastic deformation regime in these cases. Local occurrences of the Jandaíra limestone are controled by extensional faults that exhume the pre-Barreiras section, including an earlier event with N-S extension. Finally, WNWtrending extensional shear zones and faults are compatible with the Holocene stress field along the present continental margin. In the Vila Nova region, close to Icapuí, gentle normal folds with fold hinges shallowly pluging to SSW affect the lower facies of the Barreiras Formation, displaying an incipient dissolution cleavage associated with an extension lineation at high rake (a S>L fabric). Deposition of the upper facies siliciclastics is controlled by pull-apart graben structures, bordered by N-NE-trending sinistral-normal shear zones and faults, characterizing an structural inversion. Microstructures are compatible with tectonic deformation of the sedimentary pile, burried at shallow depths. The observed features point to high pore fluid pressures during deformation of the sediments, producing hydroplastic structures through mechanisms of granular flow. Such structures are overprinted by microfractures and microfaults (an essentially brittle regime), tracking the change to microfracturing and frictional shear mechanisms accompanying progressive dewatering and sediment lithification. Correlation of the structures observed at the surface with those present at depth was tested through geophysical data (Ground Penetrating Radar, seismics and a magnetic map). EW and NE-trending lineaments are observed in the magnetic map. The seismic sections display several examples of positive flower structures which affect the base of the cretaceous sediments; at higher stratigraphic levels, normal components/slips are compatible with the negative structural inversion characterized at the surface. Such correlations assisted in proposing a structural model compatible with the regional tectonic framework. The strong neogenepleistocene deformation is necessarily propagated in the subsurface, affecting the late cretaceous section (Açu and Jandaíra formations), wich host the hydrocarbon reservoirs in this portion of the Potiguar Basin. The proposed structural model is related to the dextral transcurrent/transform deformation along the Equatorial Margin, associated with transpressive terminations of E-W fault zones, or at their intersections with NE-trending lineaments, such as the Ponta Grossa-Fazenda Belém one (the LPGFB, itself controlled by a Brasiliano-age strike-slip shear zone). In a first step (and possibly during the late Cretaceous to Paleogene), this lineament was activated under a sinistral transpressional regime (antithetic to the main dextral deformation in the E-W zones), giving way to the folds in the lower facies of the Barreiras Formation, as well as the positive flower structures mapped through the seismic sections, at depth. This stage was succeeded (or was penecontemporaneous) by the extensional structures related to a (also sinistral) transtensional movement stage, associated to volcanism (Macau, Messejana) and thermal doming processes during the Neogene-Pleistocene time interval. This structural model has direct implications to hydrocarbon exploration and exploitation activities at this sector of the Potiguar Basin and its offshore continuation. The structure of the reservoirs at depth (Açu Formation sandstones of the post-rift section) may be controlled (or at least, strongly influenced) by the deformation geometry and kinematics characterized at the surface. In addition, the deformation event recognized in the Barreiras Formation has an age close to the one postulated for the oil maturation and migration in the basin, between the Oligocene to the Miocene. In this way, the described structural cenario represents a valid model to understand the conditions of hydrocarbon transport and acummulation through space openings, trap formation and destruction. This model is potentially applicable to the NW region of the Potiguar Basin and other sectors with a similar structural setting, along the brazilian Equatorial Atlantic Margin

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